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Uhlikova N, Almeida MIGS, McKelvie ID, Kolev SD. Microfluidic paper-based analytical device for the speciation of inorganic nitrogen species. Talanta 2024; 271:125671. [PMID: 38306810 DOI: 10.1016/j.talanta.2024.125671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 01/08/2024] [Accepted: 01/13/2024] [Indexed: 02/04/2024]
Abstract
A microfluidic paper-based analytical device (μPAD) utilizing gas-diffusion separation and solid-phase reduction was developed for the first time for the determination of both ammonium and nitrate, which are the dominant inorganic nitrogen species in environmental waters. The device consists of 3 filter paper layers accommodating the sample, reagent and detection zones. The reagent zone is separated from the detection zone by a semipermeable hydrophobic membrane and acts as a solid-phase reactor where nitrate is reduced to ammonia by Devarda's alloy microparticles, integrated into a μPAD for the first time. The detection zone incorporates the acid-base indicators bromothymol blue (BTB) or nitrazine yellow (NY) and changes colour in two steps. Initially the colour change is caused by ammonia generated by the reaction of ammonium and sodium hydroxide in the sample zone. This colour change is followed by a subsequent colour change as a result of the ammonia produced by the reduction of nitrate by the Devarda's alloy microparticles. The corresponding reflectance value changes are used for the quantification of the two inorganic nitrogen species in the ranges 6.5-100.0 or 2.1-15.0 mg N L-1 for ammonium and 18.2-100.0 or 4.2-15.0 mg N L-1 for nitrate when BTB or NY are used, respectively. Under optimal conditions the limits of quantification of ammonium and nitrate in the case of BTB were determined as 6.5 and 18.2 mg N L-1, respectively, while the corresponding values in the case of NY were found to be 2.1 and 4.2 mg N L-1. The newly developed μPAD was stable for 62 days when stored in a freezer and 1 day at ambient temperature. It was validated with a certified reference material and successfully applied to the determination of ammonium and nitrate in spiked environmental water samples and soil extracts.
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Affiliation(s)
- Natalie Uhlikova
- School of Chemistry, The University of Melbourne, Victoria 3010, Australia
| | - M Inês G S Almeida
- School of Chemistry, The University of Melbourne, Victoria 3010, Australia
| | - Ian D McKelvie
- School of Chemistry, The University of Melbourne, Victoria 3010, Australia
| | - Spas D Kolev
- School of Chemistry, The University of Melbourne, Victoria 3010, Australia; Department of Chemical Engineering, The University of Melbourne, Victoria 3010, Australia; Sofia University "St. Kl. Ohridski", Faculty of Chemistry and Pharmacy, 1 James Bourchier Blvd., Sofia 1164, Bulgaria.
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2
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Xu X, Nilghaz A, Wan X, Liu S, Xue M, Guo W, Tian J. A novel premixing strategy for highly sensitive detection of nitrite on paper-based analytical devices. Anal Chim Acta 2024; 1299:342417. [PMID: 38499414 DOI: 10.1016/j.aca.2024.342417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2023] [Revised: 02/04/2024] [Accepted: 02/25/2024] [Indexed: 03/20/2024]
Abstract
BACKGROUND Nitrite has been involved in many food processing techniques and its excessive consumption is closely related to the development of different diseases. Therefore, highly sensitive detection of nitrite is significant to ensure food safety. RESULT This study presents a simple and novel strategy for the highly sensitive detection of nitrite in food using paper-based analytical devices (PADs). In this proposed strategy, the nitrite present in the sample undergoes efficient diazotization when initially mixed with sulfanilamide solution before reacting with N-(1-naphthyl) ethylenediamine dihydrochloride (NED) coated on the detection region of the PAD, leading to the maximum production of colored azo compounds. Specifically, within the concentration range of 0.1-20 mg/L, the LOD and LOQ for the nitrite assay using the premixing strategy are determined as 0.053 mg/L and 0.18 mg/L, respectively which significantly surpass the corresponding values of 0.18 mg/L (LOD) and 0.61 mg/L (LOQ) achieved with the regular Griess reagent analysis. SIGNIFICANCE The study highlights the critical importance of the premixing strategy in nitrite detection. Under optimized conditions, the strategy demonstrates an excellent limit of detection (LOD) and limit of quantification (LOQ) for nitrite detection in eight different meat samples. In addition to its high precision, the strategy is applicable in the field of nitrite analysis. This strategy could facilitate rapid and cost-effective nitrite analysis in real food samples, ensuring food safety and quality analysis.
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Affiliation(s)
- Xiaohu Xu
- State Key Laboratory of Pulp and Paper Engineering, School of Light Industry and Engineering, South China University of Technology, Guangzhou, 510641, China
| | - Azadeh Nilghaz
- Institute for Frontier Materials, Deakin University, Waurn Ponds, Victoria, 3216, Australia; Drug Delivery, Disposition, and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, 3052, Australia
| | - Xiaofang Wan
- State Key Laboratory of Pulp and Paper Engineering, School of Light Industry and Engineering, South China University of Technology, Guangzhou, 510641, China
| | - Shan Liu
- School of Medicine, South China University of Technology, Guangzhou, 510006, China; Guangdong Provincial Key Laboratory of Plant Resources Biorefinery, Guangzhou, 510006, China.
| | - Meigui Xue
- Dongguan Polytechnic, Dongguan, 523808, Guangdong, China
| | - Wan Guo
- Zhejiang Kan New Mat Co Ltd, Lishui, 323300, Zhejiang, China
| | - Junfei Tian
- State Key Laboratory of Pulp and Paper Engineering, School of Light Industry and Engineering, South China University of Technology, Guangzhou, 510641, China; Guangdong Provincial Key Laboratory of Plant Resources Biorefinery, Guangzhou, 510006, China.
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Jantra J, Arsawiset S, Teepoo S, Keeratirawee K. Rapid colorimetric assay based on the oxidation of 2,2-azino-bis(3-ethylbenzothiazoline)-6-sulfonic acid-diammonium salt for nitrite detection in meat products. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART. B, PESTICIDES, FOOD CONTAMINANTS, AND AGRICULTURAL WASTES 2024; 59:72-80. [PMID: 38146233 DOI: 10.1080/03601234.2023.2297639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2023]
Abstract
This work developed a rapid colorimetric method for nitrite detection in meat products. The detection was based on the reaction of nitrite with 60 mM HCl to produce radicals which further oxidized ABTS (50 µM) to form a water-soluble blue-green product (ABTS•+). The absorbance was measured at a maximum absorption wavelength of 412.5 nm. Parameters such as concentration of HCl, concentration of ABTS and reaction time were evaluated. The absorbance was linearly proportional to the concentration of nitrite (0.1-20 µM) with the limit of detection of 0.34 µM. The proposed method was a time-saving assay since it required only 2 min to complete one measurement. There was no effect of the interference produced by other ions. The assay was robust with 2.5%RSD (n = 50). In meat product samples, high accuracy was observed with the recoveries between 100 ± 2.2% and 105 ± 3.7%. The amount of nitrite in meat products detected by the ABTS method was found in the range of 5.41 - 7.62 mg/kg. The conventional Griess method was applied to determine nitrite in the same meat products. There was no statistically significant difference between the two methods (P = 0.05).
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Affiliation(s)
- Jongjit Jantra
- King Mongkut's Institute of Technology Ladkrabang, Prince of Chumphon Campus, Pathio, Chumphon, Thailand
| | - Supattra Arsawiset
- Department of Chemistry, Faculty of Science and Technology, Rajamangala University of Technology, Thanyaburi, Pathum Thani, Thailand
| | - Siriwan Teepoo
- Department of Chemistry, Faculty of Science and Technology, Rajamangala University of Technology, Thanyaburi, Pathum Thani, Thailand
| | - Kanchalar Keeratirawee
- King Mongkut's Institute of Technology Ladkrabang, Prince of Chumphon Campus, Pathio, Chumphon, Thailand
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Silva Pereira DO, Matos MM, Fonseca A. Development of an image-based fluorometer with smartphone control for paper analytical devices. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2023; 15:4954-4963. [PMID: 37724418 DOI: 10.1039/d3ay01020a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/20/2023]
Abstract
This work describes the construction and evaluation of a fluorometer for use in paper analytical devices, using a smartphone to operate the instrument and to perform real-time image-based detection. In this approach, a circular PAD containing twenty analytical plates is rotated at 18° increments under a UV LED source, providing a sequential irradiation of plates and the detection of the luminescence with a lab-made application, capable of automatically identifying the analytical zones and collecting the RGB intensities from the selected pixels. As a proof of concept, the fluorometer performance was evaluated for the determination of quinine in beverages and riboflavin (B2 vitamin) in supplements. Quinine, which is less photoreactive, provided steady-state signals, while riboflavin, which rapidly degrades under UV photons, presented transient responses for RGB detection. For both analytes, linear calibration ranges (R2 > 0.99) were observed from 2.0 mg L-1 to 10.0 mg L-1 with limits of detection estimated at approximately 1.0 mg L-1. Nevertheless, it was demonstrated that successive additions of standard solutions to a single analytical plate of PAD could enhance the signal-to-noise ratios for less concentrated samples, acting as a pre-concentration step. In addition, suitable deviations for the signals (ca. 4.0%) and the absence of systematic errors for most samples (9 out of 11), when compared with a reference method at 95% confidence level, indicates that the proposed strategy is precise and accurate enough to be used as analytical tool for fluorescence detection in PAD.
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Affiliation(s)
- Dênis Omael Silva Pereira
- Universidade de Brasília, Instituto de Química, Campus Darcy Ribeiro, CEP 70910-900, Brasília-DF, Brazil.
| | - Mariana Mourão Matos
- Universidade de Brasília, Instituto de Química, Campus Darcy Ribeiro, CEP 70910-900, Brasília-DF, Brazil.
| | - Alexandre Fonseca
- Universidade de Brasília, Instituto de Química, Campus Darcy Ribeiro, CEP 70910-900, Brasília-DF, Brazil.
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Li Z, Liu H, Wang D, Zhang M, Yang Y, Ren TL. Recent advances in microfluidic sensors for nutrients detection in water. Trends Analyt Chem 2023. [DOI: 10.1016/j.trac.2022.116790] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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N. S. Cadeado A, C. S. Machado C, Costa MQ, Silva SG. A palm-sized wireless device for colorimetric nitrite determination in water. Microchem J 2022. [DOI: 10.1016/j.microc.2022.108138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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7
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An advantageous analytical method for the determination of fluoride in saliva exploiting smartphone-based digital-image colorimetry. CHEMICAL PAPERS 2022. [DOI: 10.1007/s11696-022-02313-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Cebrián P, Pérez-Sienes L, Sanz-Vicente I, López-Molinero Á, de Marcos S, Galbán J. Solving Color Reproducibility between Digital Devices: A Robust Approach of Smartphones Color Management for Chemical (Bio)Sensors. BIOSENSORS 2022; 12:341. [PMID: 35624642 PMCID: PMC9139083 DOI: 10.3390/bios12050341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 05/07/2022] [Accepted: 05/09/2022] [Indexed: 12/02/2022]
Abstract
In the past twelve years, digital image colorimetry (DIC) on smartphones has acquired great importance as an alternative to the most common analytical techniques. This analysis method is based on fast, low-cost, and easily-accessible technology, which can provide quantitative information about an analyte through the color changes of a digital image. Despite the fact that DIC is very widespread, it is not exempt from a series of problems that are not fully resolved yet, such as variability of the measurements between smartphones, image format in which color information is stored, power distribution of the illuminant used for the measurements, among others. This article proposes a methodology for the standardization and correction of these problems using self-developed software, together with the use of a 3D printed light box. This methodology is applied to three different colorimetric analyses using different types and brands of smartphones, proving that comparable measurements between devices can be achieved. As color can be related to many target analytes, establishing this measurement methodology can lead to new control analysis applicable to diverse sectors such as alimentary, industrial, agrarian, or sanitary.
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Affiliation(s)
- Pablo Cebrián
- Analytical Biosensors Group (GBA), Analytical Chemistry Department, Faculty of Sciences, INMA, University of Zaragoza, 50009 Zaragoza, Spain; (P.C.); (I.S.-V.); (Á.L.-M.); (S.d.M.)
| | - Leticia Pérez-Sienes
- Complex Systems Group, Polytechnic University of Madrid, ETSI Agronomy, Food and Biosystems, 28040 Madrid, Spain;
| | - Isabel Sanz-Vicente
- Analytical Biosensors Group (GBA), Analytical Chemistry Department, Faculty of Sciences, INMA, University of Zaragoza, 50009 Zaragoza, Spain; (P.C.); (I.S.-V.); (Á.L.-M.); (S.d.M.)
| | - Ángel López-Molinero
- Analytical Biosensors Group (GBA), Analytical Chemistry Department, Faculty of Sciences, INMA, University of Zaragoza, 50009 Zaragoza, Spain; (P.C.); (I.S.-V.); (Á.L.-M.); (S.d.M.)
| | - Susana de Marcos
- Analytical Biosensors Group (GBA), Analytical Chemistry Department, Faculty of Sciences, INMA, University of Zaragoza, 50009 Zaragoza, Spain; (P.C.); (I.S.-V.); (Á.L.-M.); (S.d.M.)
| | - Javier Galbán
- Analytical Biosensors Group (GBA), Analytical Chemistry Department, Faculty of Sciences, INMA, University of Zaragoza, 50009 Zaragoza, Spain; (P.C.); (I.S.-V.); (Á.L.-M.); (S.d.M.)
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Rajasulochana P, Ganesan Y, Kumar PS, Mahalaxmi S, Tasneem F, Ponnuchamy M, Kapoor A. Paper-based microfluidic colorimetric sensor on a 3D printed support for quantitative detection of nitrite in aquatic environments. ENVIRONMENTAL RESEARCH 2022; 208:112745. [PMID: 35051426 DOI: 10.1016/j.envres.2022.112745] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Revised: 12/23/2021] [Accepted: 01/13/2022] [Indexed: 05/24/2023]
Abstract
To ensure safe drinking water, it is necessary to have a simple method by which the probable pollutants are detected at the point of distribution. Nitrite contamination in water near agricultural locations could be an environmental concern due to its deleterious effects on the human population. The development of a frugal paper-based microfluidic sensor could be desirable to achieve the societal objective of providing safe drinking water. This work describes the development of a facile and cost-effective microfluidic paper-based sensor for quantitative estimation of nitrite in aquatic environments. A simple punching machine was used for fabrication and rapid prototyping of paper-based sensors without the need of any specialized equipment or patterning techniques. A reusable 3D printed platform served as the support for simultaneous testing of multiple samples. The nitrite estimation was carried out with smartphone-assisted digital image acquisition and colorimetric analysis. Under optimized experimental conditions, the variation in average grayscale intensity with concentration of nitrite was linear in the range from 0.1 to 10 ppm. The limits of detection and quantitation were 0.12 ppm and 0.35 ppm respectively. The reproducibility, expressed as relative standard deviation was 1.31%. The selectivity of nitrite detection method was determined by performing interference studies with commonly existing co-ions in water, such as bicarbonates, chloride and sulphate. The paper-based sensor was successfully applied for estimation of nitrite in actual water samples and showed high recoveries in the range of 83.5-109%. The results were in good agreement with those obtained using spectrophotometry. The developed paper-based sensor method, by virtue of its simplicity, ease of fabrication and use, could be readily extended for detection of multiple analytes in resource-limited settings.
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Affiliation(s)
- P Rajasulochana
- Department of Genetic Engineering, Bharath Institute of Science and Technology, Chennai, Tamil Nadu, 600073, India
| | - Yaswanth Ganesan
- Department of Chemical Engineering, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu, 603203, India
| | - P Senthil Kumar
- Department of Chemical Engineering, Sri Sivasubramaniya Nadar College of Engineering, Chennai, 603110, India; Centre of Excellence in Water Research (CEWAR), Sri Sivasubramaniya Nadar College of Engineering, Chennai, 603110, India.
| | - S Mahalaxmi
- Department of Chemical Engineering, Sri Sivasubramaniya Nadar College of Engineering, Chennai, 603110, India; Centre of Excellence in Water Research (CEWAR), Sri Sivasubramaniya Nadar College of Engineering, Chennai, 603110, India
| | - Fahira Tasneem
- Department of Genetic Engineering, Bharath Institute of Science and Technology, Chennai, Tamil Nadu, 600073, India
| | - Muthamilselvi Ponnuchamy
- Department of Chemical Engineering, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu, 603203, India
| | - Ashish Kapoor
- Department of Chemical Engineering, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu, 603203, India.
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10
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Tao H, Zhang Z, Cao Q, Li L, Xu S, Jiang C, Li Y, Liu Y. Ratiometric fluorescent sensors for nitrite detection in the environment based on carbon dot/Rhodamine B systems. RSC Adv 2022; 12:12655-12662. [PMID: 35480346 PMCID: PMC9039988 DOI: 10.1039/d2ra00973k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Accepted: 04/14/2022] [Indexed: 11/21/2022] Open
Abstract
A novel carbon dot/Rhodamine B-based ratiometric fluorescent probe was developed for a highly sensitivity and selective detection of nitrite (NO2−). The probe showed colour changes from blue to orange under ultraviolet light in response to NO2− with a detection limit as low as 67 nM in the range of 0 to 40 μM. A ratiometric fluorescent test paper was successfully prepared using the probe solution, which demonstrated its feasibility towards a rapid and semi-quantitative detection of NO2− in real samples. A visual ratiometric fluorescent sensor based on blue carbon dot/Rhodamine B is used to selectively detect NO2− in the environment.![]()
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Affiliation(s)
- Huihui Tao
- School of Resources and Environmental Engineering, Anhui University Hefei 230601 Anhui Province P. R. China .,Institute of Intelligent Machines, Hefei Institutes of Physical Science, Chinese Academy of Sciences Hefei 230031 P. R. China
| | - Zhao Zhang
- School of Resources and Environmental Engineering, Anhui University Hefei 230601 Anhui Province P. R. China .,Institute of Intelligent Machines, Hefei Institutes of Physical Science, Chinese Academy of Sciences Hefei 230031 P. R. China
| | - Qiao Cao
- Institute of Intelligent Machines, Hefei Institutes of Physical Science, Chinese Academy of Sciences Hefei 230031 P. R. China
| | - Lingfei Li
- Institute of Solid State Physics, Hefei Institutes of Physical Science, Chinese Academy of Sciences Hefei 230031 P. R. China
| | - Shihao Xu
- Institute of Solid State Physics, Hefei Institutes of Physical Science, Chinese Academy of Sciences Hefei 230031 P. R. China
| | - Changlong Jiang
- Institute of Solid State Physics, Hefei Institutes of Physical Science, Chinese Academy of Sciences Hefei 230031 P. R. China
| | - Yucheng Li
- School of Resources and Environmental Engineering, Anhui University Hefei 230601 Anhui Province P. R. China
| | - Yingying Liu
- Institute of Intelligent Machines, Hefei Institutes of Physical Science, Chinese Academy of Sciences Hefei 230031 P. R. China
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Thongkam T, Hemavibool K. A simple epoxy resin screen-printed paper-based analytical device for detection of phosphate in soil. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2022; 14:1069-1076. [PMID: 35195618 DOI: 10.1039/d1ay02011k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
This study develops a simple and low-cost 3D paper-based analytical device (3D PAD) for the detection of available phosphate in soil. Epoxy resin is presented as a new hydrophobic material for low-cost mass production of PADs using the screen-printing method. An optimized concentration of epoxy resin solution is screen printed onto Whatman filter paper no. 1 in an easy one-step process to create hydrophobic patterns on PADs. The epoxy resin is air dried at room temperature, without heating or UV curing. This method delivers high reproducibility, resolution, and stability, and the epoxy resin barrier is compatible with both organic solvents and aqueous solutions. The molybdenum blue method is used in this PAD to measure phosphate in a colorimetric assay. The developed 3D PAD attains a linear range of 0.5-40 mg L-1, with a limit of detection (LOD) of 0.25 mg L-1, and a limit of quantitation (LOQ) of 0.83 mg L-1. The relative standard deviation of intra-day measurements is 1.52-2.46%, and the inter-day standard deviation is 1.89-2.74%, indicating satisfactory reproducibility. This 3D PAD was tested for its ability to detect phosphate in a variety of actual soil samples and the results were validated against spectrophotometric analysis using a paired t-test, which showed high accuracy. In short, the new analytical device described in this study is simple, fast, and inexpensive to make and use, providing a versatile phosphate detection tool for many soil types, even in situations when resources are limited.
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Affiliation(s)
- Thinikan Thongkam
- Department of Chemistry, Faculty of Science, Naresuan University, Phitsanulok 65000, Thailand.
| | - Khuanjit Hemavibool
- Department of Chemistry, Faculty of Science, Naresuan University, Phitsanulok 65000, Thailand.
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Manbohi A, Ahmadi SH. Portable smartphone-based colorimetric system for simultaneous on-site microfluidic paper-based determination and mapping of phosphate, nitrite and silicate in coastal waters. ENVIRONMENTAL MONITORING AND ASSESSMENT 2022; 194:190. [PMID: 35165783 DOI: 10.1007/s10661-022-09860-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Accepted: 02/05/2022] [Indexed: 05/28/2023]
Abstract
Early and on-site detection of environmental contaminations and physicochemical parameters of seawater is increasingly preferred to guarantee hazard minimization in many settings. In this paper, we describe a combination of microfluidic paper-based sensors (µPADs) and an Android-based smartphone application (App) for simultaneous on-site quantification of phosphate (PO4-P), silicate (SiO3-Si) and nitrite (NO2-N) in coastal seawater samples. The developed App can on-site capture, process, and quantify the µPAD colorimetric outputs. This App uses an image processing algorithm for quantifying color intensity and relating the RGB components to the analyte concentrations. The GPS-tagged data can be stored on the smartphone or sent via social networks. The significant factors affecting the detection of the analytes were optimized using Box-Behnken design. Under optimized parameters, the proposed method presented the linear ranges between 5 and 100 µg L-1 for phosphate (R2 = 0.9909), 5 to 100 µg L-1 (R2 = 0.9819) for nitrite and 10 to 600 µg L-1 (R2 = 0.9933) for silicate. The LODs of the method for detection of phosphate, nitrite and silicate were 1.52 µg L-1, 0.61 µg L-1 and 3.74 µg L-1, respectively. The device was successfully used to simultaneous analyze and map the PO4-P, SiO3-Si and NO2-N of Bushehr coastal seawater samples (Iran). The results were confirmed by the lab-based conventional colorimetric methods using spectrophotometer.
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Affiliation(s)
- Ahmad Manbohi
- Department of Marine Science, Iranian National Institute for Oceanography and Atmospheric Science, 1411813389, Tehran, Iran.
| | - Seyyed Hamid Ahmadi
- Chemistry and Chemical Engineering Research Center of Iran, P.O. Box 14334-186, Tehran, Iran
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Monolithic Integrated OLED–OPD Unit for Point-of-Need Nitrite Sensing. SENSORS 2022; 22:s22030910. [PMID: 35161655 PMCID: PMC8838366 DOI: 10.3390/s22030910] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 01/14/2022] [Accepted: 01/21/2022] [Indexed: 02/06/2023]
Abstract
In this study, we present a highly integrated design of organic optoelectronic devices for Point-of-Need (PON) nitrite (NO2−) measurement. The spectrophotometric investigation of nitrite concentration was performed utilizing the popular Griess reagent and a reflection-based photometric unit with an organic light emitting diode (OLED) and an organic photodetector (OPD). In this approach a nitrite concentration dependent amount of azo dye is formed, which absorbs light around ~540 nm. The organic devices are designed for sensitive detection of absorption changes caused by the presence of this azo dye without the need of a spectrometer. Using a green emitting TCTA:Ir(mppy)3 OLED (peaking at ~512 nm) and a DMQA:DCV3T OPD with a maximum sensitivity around 530 nm, we successfully demonstrated the operation of the OLED–OPD pair for nitrite sensing with a low limit of detection 46 µg/L (1.0 µM) and a linearity of 99%. The hybrid integration of an OLED and an OPD with 0.5 mm × 0.5 mm device sizes and a gap of 0.9 mm is a first step towards a highly compact, low cost and highly commercially viable PON analytic platform. To our knowledge, this is the first demonstration of a fully organic-semiconductor-based monolithic integrated platform for real-time PON photometric nitrite analysis.
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15
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Sivakumar R, Lee NY. Recent progress in smartphone-based techniques for food safety and the detection of heavy metal ions in environmental water. CHEMOSPHERE 2021; 275:130096. [PMID: 33677270 DOI: 10.1016/j.chemosphere.2021.130096] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 02/10/2021] [Accepted: 02/21/2021] [Indexed: 05/14/2023]
Abstract
Emerging smartphone-based point-of-care tests (POCTs) are cost-effective, precise, and easy to implement in resource-limited areas. Thus, they are considered a potential alternative to conventional diagnostic testing. This review explores food safety and the detection of metal ions in environmental water based on unprecedented smartphone technology. Specifically, we provide an overview of various methods used for target analyte detection (antibiotics, enzymes, mycotoxins, pathogens, pesticides, small molecules, and metal ions), such as colorimetric, fluorescence, microscopic imaging, and electrochemical methods. This paper performs a comprehensive review of smartphone-based POCTs developed in the last three years (2018-2020) and evaluates their relative advantages and limitations. Moreover, we discuss the imperative role of new technology in the progress of POCTs. Sensor materials (metal nanoparticles, carbon dots, quantum dots, organic substrates, etc.) and detection techniques (paper-based, later flow assay, microfluidic platform, etc.) involved in POCTs based on smartphones, and the challenges faced by these techniques, are addressed.
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Affiliation(s)
- Rajamanickam Sivakumar
- Department of Industrial Environmental Engineering, College of Industrial Environmental Engineering, Gachon University, 1342 Seongnam-daero, Sujeong-gu, Seongnam-si, Gyeonggi-do, 13120, South Korea
| | - Nae Yoon Lee
- Department of BioNano Technology, Gachon University, 1342 Seongnam-daero, Sujeong-gu, Seongnam-si, Gyeonggi-do, 13120, South Korea.
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Saranchina NV, Slizhov YG, Vodova YM, Murzakasymova NS, Ilyina AM, Gavrilenko NA, Gavrilenko MA. Smartphone-based colorimetric determination of fluoride anions using polymethacrylate optode. Talanta 2021; 226:122103. [PMID: 33676659 DOI: 10.1016/j.talanta.2021.122103] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 01/07/2021] [Accepted: 01/09/2021] [Indexed: 11/30/2022]
Abstract
We developed a new transparent polymer optode based on polymethacrylate with Zr(IV) and alizarin red complex immobilized into it for digital colorimetric and solid-phase spectrophotometric determination of fluoride anions. The matrix changes its colour from purple to yellow after it contacts fluoride anion. We developed a processing algorithm for coloured images which helps calculate mean value for the RGB colour-coordinate system in a selected optode image and translates it into a fluoride concentration value. The analytical signal of the suggested method has a linearity range of 0.1-30 mg⋅L-1 with the detection limit 0.03 mg⋅L-1. Compared to other methods, the modified polymethacrylate matrix is actually a ready-to-use colorimetric system offering rapid results for drinking water quality control.
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Affiliation(s)
| | | | | | | | - A M Ilyina
- Tomsk Polytechnic University, Tomsk, Russia
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17
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Petrenko D, Marchenko D, Vasil'ev N. Zirconium gallocyanin MS complex as a highly selective reagent for the spectophotometric determination of fluoride. Microchem J 2021. [DOI: 10.1016/j.microc.2021.106081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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18
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Silver-miang nanocomposites: A green, rapid and simple approach for selective determination of nitrite in water and meat samples. Microchem J 2021. [DOI: 10.1016/j.microc.2020.105879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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19
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Distance-Based Detection of Ag+ with Gold Nanoparticles-Coated Microfluidic Paper. JOURNAL OF ANALYSIS AND TESTING 2021. [DOI: 10.1007/s41664-021-00157-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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20
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An environmentally friendly microfluidic paper-based analytical device for simultaneous colorimetric detection of nitrite and nitrate in food products. Microchem J 2020. [DOI: 10.1016/j.microc.2020.105412] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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21
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Novel microfluidic paper-based analytical devices (μPADs) for the determination of nitrate and nitrite in human saliva. Talanta 2020; 219:121183. [DOI: 10.1016/j.talanta.2020.121183] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 05/14/2020] [Accepted: 05/16/2020] [Indexed: 12/15/2022]
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22
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Thongkam T, Rungsirisakun R, Hemavibool K. A simple paper-based analytical device using UV resin screen-printing for the determination of ammonium in soil. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2020; 12:4649-4656. [PMID: 32895682 DOI: 10.1039/d0ay01180k] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
This study reports a convenient and low cost paper-based analytical device (PAD) for measuring ammonium in soil. This PAD has been developed using an inexpensive UV resin solution, as a new hydrophobic material, with a screen-printing method to create hydrophobic areas. The paper-based colorimetric device was developed using a modified Berthelot reaction in which salicylate and dichloroisocyanurate are used in order to produce a green compound of 2-2 dicarboxyindophenol in the presence of ammonium. The concentration of ammonium is proportional to the intensity of the resulting green color, as analysed by ImageJ software. A variety of tests was carried out to optimize and evaluate various aspects of the PAD's fabrication and utilization. A linear range was obtained in the range of 10-100 mg L-1 with a limit of detection and limit of quantitation of 0.5 mg L-1 and 1.7 mg L-1, respectively. The relative standard deviation of intra-day measurements was 3.0% and the inter-day precision was 3.2% with good reproducibility. When recovery of ammonium added to samples was evaluated it ranged from 95.5 to 107.5%. The PAD was applied to detect ammonium in a variety of actual soil samples, and the results were validated against spectrophotometric results using a paired t-test, showing good accuracy. A convenient color comparison chart was also created on paper to enable the user to interpret the color results without the need for a color scanner. This developed PAD is fast, easy, inexpensive, and provides an alternative to existing methods for the determination of ammonium in soil.
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Affiliation(s)
- Thinikan Thongkam
- Department of Chemistry, Faculty of Science, Naresuan University, Phitsanulok 65000, Thailand.
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23
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Mako TL, Levenson AM, Levine M. Ultrasensitive Detection of Nitrite through Implementation of N-(1-Naphthyl)ethylenediamine-Grafted Cellulose into a Paper-Based Device. ACS Sens 2020; 5:1207-1215. [PMID: 32162520 DOI: 10.1021/acssensors.0c00291] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Reported herein is the immobilization of N-(1-naphthyl)ethylenediamine (NED) on cellulose via an epichlorohydrin (ECH)-based covalent attachment and the implementation of the functionalized cellulose into an ultrasensitive, paper-based device for nitrite detection. The reported functionalization procedure resulted in a 12.9-fold higher functionalization density than the density that results from the previously reported procedures, and the subsequent device allows for nitrite detection limits in synthetic freshwater and real seawater of 0.26 and 0.22 μM, respectively. The sensor is efficient in a wide range of temperature, humidity, turbidity, and salinity conditions and has been successfully applied for nitrite detection in real water samples.
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Affiliation(s)
- Teresa L. Mako
- Department of Chemistry, University of Rhode Island, 140 Flagg Road, Kingston, Rhode Island 02881, United States
| | - Adelaide M. Levenson
- Department of Chemistry, University of Rhode Island, 140 Flagg Road, Kingston, Rhode Island 02881, United States
| | - Mindy Levine
- Department of Chemistry, University of Rhode Island, 140 Flagg Road, Kingston, Rhode Island 02881, United States
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24
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Pena-Pereira F, Matesanz Ó, Lavilla I, Bendicho C. A paper-based gas sensor for simultaneous noninstrumental colorimetric detection of nitrite and sulfide in waters. J Sep Sci 2020; 43:1908-1914. [PMID: 32079045 DOI: 10.1002/jssc.201901339] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2020] [Revised: 02/15/2020] [Accepted: 02/16/2020] [Indexed: 12/20/2022]
Abstract
The use of paper-based devices in combination with noninstrumental detection systems is becoming increasingly important in the analytical field due to its simplicity, rapidity, and low cost. However, their use for determination of volatile analyte derivatives is still relatively scarce. The present work reports on the assessment of a paper-based gas-sensing approach for the simultaneous noninstrumental colorimetric detection of nitrite and sulfide. Colorimetric systems based on the Griess and methylene blue assays, formation of colored metallic sulfides, and interaction/reaction with in situ generated metallic nanoparticles were preliminary evaluated. Then, the effect of experimental variables affecting the analytical performance of the paper-based gas sensor was studied with two digitization systems, namely a scanner and a smartphone. Under optimal conditions, the developed system yielded limits of detection of 0.055 and 0.005 mg/L for nitrite and sulfide, respectively. The repeatability, expressed as relative standard deviation, was found to be 5.9 and 6.7% for nitrite and sulfide, respectively. The proposed method was finally applied to the analysis of water samples, showing recoveries in the range of 95-105%.
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Affiliation(s)
- Francisco Pena-Pereira
- Analytical and Food Chemistry Department, Faculty of Chemistry, Marine Research Center (CIM), University of Vigo, Campus As Lagoas-Marcosende s/n, Vigo, 36310, Spain
| | - Óscar Matesanz
- Analytical and Food Chemistry Department, Faculty of Chemistry, Marine Research Center (CIM), University of Vigo, Campus As Lagoas-Marcosende s/n, Vigo, 36310, Spain
| | - Isela Lavilla
- Analytical and Food Chemistry Department, Faculty of Chemistry, Marine Research Center (CIM), University of Vigo, Campus As Lagoas-Marcosende s/n, Vigo, 36310, Spain
| | - Carlos Bendicho
- Analytical and Food Chemistry Department, Faculty of Chemistry, Marine Research Center (CIM), University of Vigo, Campus As Lagoas-Marcosende s/n, Vigo, 36310, Spain
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25
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Solanki S, Pandey CM, Gupta RK, Malhotra BD. Emerging Trends in Microfluidics Based Devices. Biotechnol J 2020; 15:e1900279. [PMID: 32045505 DOI: 10.1002/biot.201900279] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 01/28/2020] [Indexed: 01/03/2023]
Abstract
One of the major challenges for scientists and engineers today is to develop technologies for the improvement of human health in both developed and developing countries. However, the need for cost-effective, high-performance diagnostic techniques is very crucial for providing accessible, affordable, and high-quality healthcare devices. In this context, microfluidic-based devices (MFDs) offer powerful platforms for automation and integration of complex tasks onto a single chip. The distinct advantage of MFDs lies in precise control of the sample quantities and flow rate of samples and reagents that enable quantification and detection of analytes with high resolution and sensitivity. With these excellent properties, microfluidics (MFs) have been used for various applications in healthcare, along with other biological and medical areas. This review focuses on the emerging demands of MFs in different fields such as biomedical diagnostics, environmental analysis, food and agriculture research, etc., in the last three or so years. It also aims to reveal new opportunities in these areas and future prospects of commercial MFDs.
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Affiliation(s)
- Shipra Solanki
- Department of Biotechnology, Delhi Technological University, Shahbad Daulatpur, Delhi, 110042, India.,Department of Applied Chemistry, Delhi Technological University, Shahbad Daulatpur, Delhi, 110042, India
| | - Chandra M Pandey
- Department of Applied Chemistry, Delhi Technological University, Shahbad Daulatpur, Delhi, 110042, India
| | - Rajinder K Gupta
- Department of Applied Chemistry, Delhi Technological University, Shahbad Daulatpur, Delhi, 110042, India
| | - Bansi D Malhotra
- Department of Biotechnology, Delhi Technological University, Shahbad Daulatpur, Delhi, 110042, India
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26
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Vidal E, Lorenzetti AS, Aguirre MÁ, Canals A, Domini CE. New, inexpensive and simple 3D printable device for nephelometric and fluorimetric determination based on smartphone sensing. RSC Adv 2020; 10:19713-19719. [PMID: 35515453 PMCID: PMC9054129 DOI: 10.1039/d0ra02975k] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 05/12/2020] [Indexed: 11/21/2022] Open
Abstract
A new, inexpensive and easy to use 3D printable device was developed for nephelometric and fluorimetric determination. Its applicability was tested for the quantification of quinine in tonic drinks and sulfate in natural water with good analytical accuracy. In this way, sulfate determination was carried out by nephelometry using a red LED, while quinine was determined using a blue LED by fluorimetry. A smartphone camera was used to take the pictures and afterwards transform them into the RGB color space using the software ImageJ by a personal computer. The linear range was 2.0–50.0 mg L−1 for sulfate with a LOD of 0.13 mg L−1, and the corresponding quantification limit (LOQ) was 0.43 mg L−1. The linear range for quinine was from 0.42 to 3.10 mg L−1. The LOD and LOQ were 0.11 mg L−1 and 0.38 mg L−1, respectively. A new, inexpensive and easy to use 3D printable device was developed for nephelometric and fluorimetric determination.![]()
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Affiliation(s)
- Ezequiel Vidal
- INQUISUR
- Departamento de Química
- Universidad Nacional del Sur (UNS)-CONICET
- 8000 Bahía Blanca
- Argentina
| | - Anabela S. Lorenzetti
- INQUISUR
- Departamento de Química
- Universidad Nacional del Sur (UNS)-CONICET
- 8000 Bahía Blanca
- Argentina
| | - Miguel Ángel Aguirre
- Departamento de Química Analítica, Nutrición y Bromatología
- Instituto Universitario de Materiales
- Universidad de Alicante
- 03080 Alicante
- Spain
| | - Antonio Canals
- Departamento de Química Analítica, Nutrición y Bromatología
- Instituto Universitario de Materiales
- Universidad de Alicante
- 03080 Alicante
- Spain
| | - Claudia E. Domini
- INQUISUR
- Departamento de Química
- Universidad Nacional del Sur (UNS)-CONICET
- 8000 Bahía Blanca
- Argentina
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27
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Porto IS, Santos Neto JH, dos Santos LO, Gomes AA, Ferreira SL. Determination of ascorbic acid in natural fruit juices using digital image colorimetry. Microchem J 2019. [DOI: 10.1016/j.microc.2019.104031] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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28
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Pires NMM, Dong T, Yang Z. A fluorimetric nitrite biosensor with polythienothiophene-fullerene thin film detectors for on-site water monitoring. Analyst 2019; 144:4342-4350. [PMID: 31192320 DOI: 10.1039/c8an02441c] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
A novel fluorimetric sensor for highly sensitive nitrite detection on the site is presented in this study. The proposed on-chip approach comprises the use of integrated polymer photodetectors to detect light from fluorescence reactions with a diaminofluorescein probe. The detectors were prepared with a heterostructured nanofilm of polythieno[3,4-b]thiophene/benzodithiophene and (6,6)-phenyl-C71-butyric-acid methyl-ester as a photoactive layer. Prior to fluorimetric detection, the quality of the spin-coated photoactive layer was characterized via nano-morphology and current-density measurements. Nitrite assays were conducted on a poly(methyl methacrylate) microchannel chip, to which polythienothiophene-C71 based detectors were aligned. Results of signal-to-noise ratio determination have indicated a detection limit below 0.55 μM, lower than the 0.1 mg L-1 maximum limit of operation in recirculating aquaculture systems for farming Atlantic salmon Salmo salar. An increase of the nitrite concentration to toxic levels may therefore be possible to detect. The fluorimetric sensor exhibited good linearity over three orders of magnitude and acceptable detection reproducibility, which confirmed its analytical value. Further tests revealed great promise of the integrated biosensor device for detecting nitrite in aquaculture-relevant samples with high precision. The approach reported hereby may provide impetus to in situ analytical tools for monitoring water quality at aquaculture facilities, the food industries or water monitoring stations.
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Affiliation(s)
- Nuno Miguel Matos Pires
- Chongqing Key Laboratory of Micro-Nano Systems and Smart Transduction, Collaborative Innovation Center on Micro-Nano Transduction and Intelligent Eco-Internet of Things, Chongqing Key Laboratory of Colleges and Universities on Micro-Nano Systems Technology and Smart Transducing, National Research Base of Intelligent Manufacturing Service, Chongqing Technology and Business University, Nan'an District, Chongqing 400067, China and Department of Microsystems - IMS, Faculty of Technology, Natural Sciences and Maritime Sciences, University of South-Eastern Norway-USN, P.O. Box 235, 3603 Kongsberg, Norway. and Centre for Environmental Radioactivity (CERAD CoE), Norwegian University of Life Sciences (NMBU), Faculty of Environmental Sciences and Natural Resource Management, P.O. Box 5003, NO-1432 Ås, Norway
| | - Tao Dong
- Department of Microsystems - IMS, Faculty of Technology, Natural Sciences and Maritime Sciences, University of South-Eastern Norway-USN, P.O. Box 235, 3603 Kongsberg, Norway.
| | - Zhaochu Yang
- Chongqing Key Laboratory of Micro-Nano Systems and Smart Transduction, Collaborative Innovation Center on Micro-Nano Transduction and Intelligent Eco-Internet of Things, Chongqing Key Laboratory of Colleges and Universities on Micro-Nano Systems Technology and Smart Transducing, National Research Base of Intelligent Manufacturing Service, Chongqing Technology and Business University, Nan'an District, Chongqing 400067, China
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29
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Monteiro T, Gomes S, Jubete E, Añorga L, Silveira CM, Almeida MG. A quasi-reagentless point-of-care test for nitrite and unaffected by oxygen and cyanide. Sci Rep 2019; 9:2622. [PMID: 30796298 PMCID: PMC6385495 DOI: 10.1038/s41598-019-39209-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Accepted: 01/14/2019] [Indexed: 12/17/2022] Open
Abstract
The ubiquitous nitrite is a major analyte in the management of human health and environmental risks. The current analytical methods are complex techniques that do not fulfil the need for simple, robust and low-cost tools for on-site monitoring. Electrochemical reductase-based biosensors are presented as a powerful alternative, due to their good analytical performance and miniaturization potential. However, their real-world application is limited by the need of anoxic working conditions, and the standard oxygen removal strategies are incompatible with point-of-care measurements. Instead, a bienzymatic oxygen scavenger system comprising glucose oxidase and catalase can be used to promote anoxic conditions in aired environments. Herein, carbon screen-printed electrodes were modified with cytochrome c nitrite reductase together with glucose oxidase and catalase, so that nitrite cathodic detection could be performed by cyclic voltammetry under ambient air. The resulting biosensor displayed good linear response to the analyte (2–200 µM, sensitivity of 326 ± 5 mA M−1 cm−2 at −0.8 V; 0.8–150 µM, sensitivity of 511 ± 11 mA M−1 cm−2 at −0.5 V), while being free from oxygen interference and stable up to 1 month. Furthermore, the biosensor’s catalytic response was unaffected by the presence of cyanide, a well-known inhibitor of heme-enzymes.
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Affiliation(s)
- Tiago Monteiro
- UCIBIO, REQUIMTE, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2829-516, Monte de Caparica, Portugal
| | - Sara Gomes
- UCIBIO, REQUIMTE, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2829-516, Monte de Caparica, Portugal
| | - Elena Jubete
- CIDETEC, Sensors Unit, Parque Científico y Tecnológico de San Sebastián, P° Miramón 196, 2014 Donostia, San Sebastián, Spain
| | - Larraitz Añorga
- CIDETEC, Sensors Unit, Parque Científico y Tecnológico de San Sebastián, P° Miramón 196, 2014 Donostia, San Sebastián, Spain
| | - Célia M Silveira
- UCIBIO, REQUIMTE, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2829-516, Monte de Caparica, Portugal.,Instituto de Tecnologia Química e Biológica António Xavier, Universidade NOVA de Lisboa, Av. da República, 2780-157, Oeiras, Portugal
| | - Maria Gabriela Almeida
- UCIBIO, REQUIMTE, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2829-516, Monte de Caparica, Portugal. .,Centro de Investigação Interdisciplinar Egas Moniz (CiiEM), Instituto Superior de Ciências da Saúde Egas Moniz, Campus Universitário, Quinta da Granja, 2829-511, Caparica, Portugal.
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